complete 24392.rs 24819.rs

storage/zeta/rs/completed/24392.rs

@@ -0,0 +1,74 @@
+use std::io::stdin;
+
+enum Pane {
+    Normal,
+    Reinforced,
+}
+
+fn main() {
+    let mut line = String::new();
+    stdin().read_line(&mut line).unwrap();
+
+    let mut iter = line.trim().split(' ').map(|x| x.parse::<usize>().unwrap());
+
+    let n = iter.next().unwrap();
+    let m = iter.next().unwrap();
+
+    let panes = (0..n)
+        .map(|_| {
+            line.clear();
+            stdin().read_line(&mut line).unwrap();
+            line.split(' ')
+                .map(|x| match x.chars().next().unwrap() {
+                    '0' => Pane::Normal,
+                    '1' => Pane::Reinforced,
+                    _ => unreachable!(),
+                })
+                .collect::<Vec<Pane>>()
+        })
+        .collect::<Vec<Vec<Pane>>>()
+        .into_iter()
+        .rev()
+        .collect::<Vec<Vec<Pane>>>();
+
+    /*
+       Calc All Possible Paths
+    */
+
+    let mut dp = vec![vec![0u64; m]; n];
+
+    panes[0]
+        .iter()
+        .enumerate()
+        .for_each(|(i, pane)| match pane {
+            Pane::Normal => dp[0][i] = 0,
+            Pane::Reinforced => dp[0][i] = 1,
+        });
+
+    for i in 1..n {
+        for j in 1..(m - 1) {
+            dp[i][j] = match panes[i][j] {
+                Pane::Normal => 0,
+                Pane::Reinforced => {
+                    let left = dp[i - 1][j - 1];
+                    let right = dp[i - 1][j + 1];
+                    let centre = dp[i - 1][j];
+                    (left + right + centre) % 1_000_000_007
+                }
+            };
+        }
+        dp[i][0] = match panes[i][0] {
+            Pane::Normal => 0,
+            Pane::Reinforced => (dp[i - 1][0] + dp[i - 1][1]) % 1_000_000_007,
+        };
+        dp[i][m - 1] = match panes[i][m - 1] {
+            Pane::Normal => 0,
+            Pane::Reinforced => (dp[i - 1][m - 2] + dp[i - 1][m - 1]) % 1_000_000_007,
+        }
+    }
+
+    let res = dp[n - 1]
+        .iter()
+        .fold(0u64, |acc, x| (acc + x) % 1_000_000_007);
+    println!("{}", res);
+}